Electrical switching apparatus



Patented Dec. 16, 1947 UNITED STATES PATENT OFFICE 4 Claims.

This invention relates to electrical switching apparatus and more particularly to mechanism of that character for actuating signals such as door chimes and the like.

It is common practice to operate single tone chimes by means including solenoids having armatures provided with suitable hammers for striking the chimes. In the operation of multitone chimes, more extensive equipment is required, such as electric motors, relays, and the like. While the multi-tone chime is much more desirable than the single tone, its cost is, in many cases, prohibitive.

The primary aim of the instant invention is the provision of a multi-tone chime actuated with equipment that can be produced at low cost.

A further aim of the invention is to provide a chime or the above character having means embodied therein for controlling the time period between each successive sounding of a series of chime units.

It is another object of this invention to provide a chime that will complete a predetermined course of operation, regardless of whether the push button switch is pressed only once or repeatedly at short intervals.

Further objects of the invention will become apparent during the course of the following specification, referring to the accompanying drawing wherein:

Fig. 1 is a diagrammatical view of the chime assembly, showing the master solenoid and chime and switch actuating solenoids in central section; and

Fig. 2 is a cross section taken on line IIII of Fig. 1.

The assembly comprising the multi-tone chime and its actuating mechanism consists generally of a master solenoid I6, sound tubes I2, l4, I6 and I3 respectively operated by solenoids 20, 22, 24 and 26, a mercury switch 28, and a solenoid 3B operably connected therewith.

The master solenoid I is relatively large and built up of a cylinder 32 of insulating material having a surrounding coil 34 extending along the greater portion of its length. A core 35 formed either solidly as shown on comprising a tubing section to reduce the weight thereof, is mounted for longitudinal reciprocation in the cylinder 32 and is provided with a groove 38 adapted to be engaged by the inner end of a screw 40 threaded through the cylinder wall, thereby preventing rotative movement of the core relative to the cylinder. An inwardly directed flange 42 on the lower end of cylinder 32 limits the downward movement of core 36. A slot 44 in the flange is aligned with a groove 46 in cylinder 32, to receive a contact bar 48 having an outwardly bent upper end projected through an opening 50 in the cylinder wall.

Fitted into the cylinder wall on a line diametrically opposite bar 68, are a series of contact points 52, 54, 56, 58, and 62. An opening 63 extending transversely through core 36 near its lower end is provided to receive the reduced ends of opposed brushes 64 and 66 adapted to respectively engage bar 48 and the series of contact points, and urged outwardly against the cylinder wall by a spring 68 interposed between the brushes.

The upper end of cylinder 32 is preferably provided with a removable cap I0 having a port I2 normally closed by a downwardly seating relief valve Id. The passage of air through a second port 16 formed in cap I0 is controlled by an adjustable needle valve I8. A piston secured in any convenient manner to the upper end of core 36, as by means of a screw 82, permits free upward movement of the core in cylinder 32 but retards downward movement thereof for a purpose later to be more fully described.

Solenoid 2! comprises an insulating cylinder 34 surrounded by a pair of coils 86 and 88 and provided with a core 89 for striking sounding plate 90 of tube I2. In like manner, solenoid 22 has coils 92 and 94 wound thereon and its core 95 is adapted to strike plate 98 of tube I4. Similarly, solenoid 24 includes windings I20 and I02, and core IE4 for striking plate I86 of tube [6. Coils I98 and H0 are wound on cylinder II2 of solenoid 26 and core I I4 reciprocable in the cylinder is arranged to strike plate IIG of tube .I8.

Mercury switch 28 is provided with pairs of points are and H2 and is pivotally mounted on a bracket I24 by means of an arm I26 operably connected with the core or armature I28 of solenoid 38. The latter is further provided with spaced windings I36 and I32.

A battery 3 5 or other source of electrical energy and a push button switch I33 complete the list of units of the assembly which are electrically connected as follows:

One of each of the pairs of points I26 and I22 on mercury switch 28 is connected by conductor 538 with the positive post of battery I34. This post is likewise connected by conductor MD with each of coils I30 and I 32 of solenoid 30. A wire Hi2 connects the negative post of battery I34 with the lower end of contact bar 48, the upper end of which is joined to windings 34 of master solenoid I6. Contact point 52 is connected by conductor I44 with coil I36 of solenoid 36, a branch I46 of conductor I44 being connected with coil 86 of solenoid 26. Wire I48 has branches I56 and I52 respectively connecting windings 88 and 92 of solenoids 26 and 22 with contact point 54. A conductor I54 having branches I56 and I58 respectively leading to coils 94 and I66 of solenoids 22 and 24, connects the latter with contact point 56. Contact point 58 is connected by wire I66 and its branches I62 and I64 with coils I62 and I66 or solenoids 24 and 26 respectively. A conductor I66 connects point 66 with winding H6 of solenoid 26. One of the points of pair I26 of mercury switch 28, is connected to winding 34 of master solenoid I6 by conductor I68 having the switch I36 interposed therein. A conductor I16 leading from the positive point of pair I22 of switch 23 is provided with branches I12, I14, I16 and I16, each having a divided end connected respectively with the windings of solenoids 26, 22, 24 and Contact point 62 is connected by conductor I66 with winding I32 of solenoid 36.

Assuming the parts to be in the position shown in Fig. 1 of the drawing, operation of the switching mechanism would be as follows:

Upon closing switch I36, current flows from battery I34 through conductor I42, bar 48, winding 34 of solenoid I6, conductor I68, points I26, and wire I38 to energize coil 34 and draw core 36 to its uppermost position. Pressure tending to build up in cylinder 32 is relieved through valved port 12. When push button I36 is released, the circuit through coil 34 is broken and core or armature 36 begins to descend under the action of gravity. Because of the provision of piston 86 on core 36, a vacuum is formed in the cylinder above the piston, the strength of the vacuum being controlled by needle valve 18. Accordingly, core 36 may be allowed to drop rapidly or to move downwardly at a very slow rate of speed.

When brush 66 comes into contact with point 52, brush 64 will also be in contact with bar 48, thereby closing the circuit from battery I34 through conductor I42, bar 48, brush 64, spring 68, brush 66, contact 52, wire I44, coil I36 of s01enoid 36, and wire I46. Energization of winding I36 reverses the position of mercury switch 28. As a result, current can also flow from contact 52 through wire I44, branch I46, coil 86 of solenoid 26, branch I12, conductor I16, contact points I22, and wire I38. This causes armature 89 to be drawn away from sound plate 96.

As core 36 continues its downward travel within cylinder 32, brush 66 leaves contact 52 and next wipesalong contact 54. Thereupon current flows through wire I42, bar 48, brush 64, spring 68, brush 66, wire I48, branch I56, winding 86, branch I12, conductor I16, points I22, and wire I33 to energize winding 88 and cause armature 66 to strike round plate 66. Simultaneously, current also flows through branch I52 of wire I48 and through coil 62 and branch I14 to retract armature 96.

The results from successive engagement of brush 66 with each of contacts 56, 58 and 66 is exactly like that described in connection with contact 54, i. e., armatures 96, I64 and H4 are first retracted and then caused to strike their respective sound plates 98, I66 and H6, whereby a series or" difierently pitched signals are consecutively sounded as armature 36 travels downwardly.

When contact point 62 is reached by brush 66 current flows through wire I42, bar 48, brush 64,

spring 68, brush 66, point 62, wire I86, winding I32, and conductor I46 to again return mercury switch 28 to its original position.

From the foregoing it will be clear that when switch I36 is closed, the cycle of operation will continue until it is completed, even though in the interim the push button is repeatedly pressed.

It is conceivable that various modifications might be made without departing from the spirit of this invention, and it is desired therefore, to be limited only by the scope of the appended claims.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. In an electrical switching system for chimes, a first electrical circuit having a stationary contact bar and a series of spaced contact points spaced therefrom; a second circuit having a master solenoid provided with a reciprocable core having a brush slidable on said contact bar and successively engageable with said series of contacts; a double coil solenoid in said first circuit joined to each of certain of the series of contacts to reciprocate a core of each as the coils are alternately energized; a double throw switch for controlling the flow of current through the second circuit to the master solenoid core when in one position and through the first circuit to the coils of the double coil solenoids when in the other position; and a two coil solenoid for shifting the switch to each of its two positions, said two coil solenoid having a third electrical circuit joined to the first and last contacts of the series thereof to cause the double throw switch to supply current to the master solenoid until the brush reaches the last of the series of contacts as the core and brush of the solenoid travels in one direction and to cause the said switch to supply current to the double coil solenoids as the core and brush travel in the opposite direction over the contacts to successively supply current to the coils of the two coil solenoids.

2. In an electrical switching system for chimes, a first electrical circuit having a stationary contact bar and a series of spaced contact points spaced therefrom; a second circuit having a master solenoid provided with a reciprocable core having a brush slidable on said contact bar and successively engageable with said series of contacts; a double coil solenoid in said first circuit joined to each of certain of the series of contacts to reciprocate a core of each as the coils are alternately energized; a double throw switch for controlling the flow of current through the second circuit to the master solenoid core when in one position and through the first circuit to the coils f the double coil solenoids when in the other position; and a two coil solenoid for shifting the switch to each of its two positions, said two coil solenoid having a third electrical circuit joined to the first and last contacts of the series thereof to cause the double throw switch to supply current to the master solenoid until the brush reaches the last of the series of contacts as the core and brush of the solenoid travels in one direction and to cause the said switch to supply current to the double coil solenoids as the core and brush travel in the opposite direction over the contacts to successively supply current to the coils of the two coil solenoids, said double coil solenoids being connected to the series of contacts to cause energization of the coils in sequence to successively reciprocate the cores of the double coil solenoids.

3. In an electrical switching apparatus, a

source of electrical energy; an electrical circuit having connection with said source of energy; a number of solenoids, each having a pair of windings, said windings being series-connected within said electrical circuit; a, plurality of normally open switches in said circuit, each operable when closed to close said circuit through at least one of said windings respectively, said switches comprising a plurality of spaced contact points, an elongated contact bar common to all of said contact points and spaced therefrom, and a reciprocable member adapted to successively bridge said contact points with the contact bar when reciprocated therealong; a control switch in said circuit, said control switch being normally open as the said member moves in one direction along the contact bar and the contact points; and means operable to close said control switch upon interconnecting one of said contact points with the contact bar as the member moves in the opposite direction.

4. In an electrical switching apparatus, a nonmagnetic cylinder; an electric coil circumscribing said cylinder near one end thereof; a reciprocable magnetic core within said cylinder; a row of spaced contact points within the cylinder near its opposite end extending longitudinally of said cylinder; an elongated contact bar in the cylinder in opposed, substantially parallel relationship to said contact points; an electric conducting brush carried by the said core and slidable at one end thereof on said contact bar and at its opposite end across said contact points when the core reciprocates in the cylinder; a

source of electrical current; an electrical circuit interconnecting said source of current and said coil for moving the core to said one end of the cylinder when the circuit is energized, said core movin to the opposite end of the cylinder by force of gravity; a second electrical circuit having connection with said contact bar and certain of said contact points; a solenoid in said second circuit for each of said certain contact points respectively; a third electrical circuit having connection with the two outermost contact points of said row thereof and said source of current; a switch movable to and from a position connecting said second circuit with said source of current; and electrical means in said third circuit operably connected to said switch for moving said switch to said position when one of said outermost contact points is eng ed by the brush and from said position when the other outermost contact point is engaged by said brush.

MILO F. MILLER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 568,947 Hicks Oct. 6, 1896 1,873,193 Frennell Aug. 23, 1932 1,957,877 Young May 8, 1934 2,186,498 Riggs Jan. 9, 1940 2,206.83? Edwards July 2, 1940 2,296,554 Hinchman Sept. 22, 1942 

